Fixing a deadlock in record when the working copy can lock the transaction (not many working copy implementations do that)

pmeunier

May 12, 2022, 7:50 PM

ZHS7GTREKJ76WVU4PHIOZNEPEURQYJL3W4BT6XH2CN5G5VRPKL4QC

Dependencies

• [2] FXEDPLRI Resurrecting tests, and type cleanup (no need for Arc<RwLock<…>> anymore)
• [3] ZDK3GNDB Tag transactions (including a massive refactoring of errors)
• [4] I24UEJQL Various post-fire fixes
• [*] SXEYMYF7 Fixing the bad changes in history (unfortunately, by rebooting).

Change contents

• replacement in libpijul/src/record.rs at line 410
  [3.47581]→[2.97127:97231](∅→∅),[2.97231]→[3.47703:47765](∅→∅),[3.47703]→[3.47703:47765](∅→∅)
  − let mut txn = txn.write();

  − let mut channel = channel.r.write();

  − let mut graph = txn.graph(&mut *channel);
  [3.47581]

  [3.47765]
  + let txn = txn.read();

  + let channel = channel.r.read();

  + let graph = txn.graph(&*channel);
• replacement in libpijul/src/record.rs at line 414
  [3.47816]→[3.47816:47887](∅→∅)
  − &mut *txn,

  − &mut graph,
  [3.47816]

  [2.97232]
  + &*txn,

  + &graph,